Properly pass kwargs to metaclass in builtin_build_class

vm/src/builtins.rs

@@ -959,7 +959,10 @@ pub fn builtin_build_class_(
 
     let class = vm.invoke(
         metaclass.as_object(),
-        vec![name_obj, bases, namespace.into_object()],
+        (
+            Args::from(vec![name_obj, bases, namespace.into_object()]),
+            kwargs,
+        ),
     )?;
     cells.set_item("__class__", class.clone(), vm)?;
     Ok(class)

vm/src/function.rs

@@ -44,6 +44,16 @@ impl From<PyObjectRef> for PyFuncArgs {
     }
 }
 
+impl From<(Args, KwArgs)> for PyFuncArgs {
+    fn from(arg: (Args, KwArgs)) -> Self {
+        let Args(args) = arg.0;
+        let KwArgs(kwargs) = arg.1;
+        PyFuncArgs {
+            args,
+            kwargs: kwargs.into_iter().collect(),
+        }
+    }
+}
 impl From<(&Args, &KwArgs)> for PyFuncArgs {
     fn from(arg: (&Args, &KwArgs)) -> Self {
         let Args(args) = arg.0;
@@ -293,6 +303,11 @@ impl<T> Args<T> {
         self.0
     }
 }
+impl<T> From<Vec<T>> for Args<T> {
+    fn from(v: Vec<T>) -> Self {
+        Args(v)
+    }
+}
 
 impl<T: PyValue> Args<PyRef<T>> {
     pub fn into_tuple(self, vm: &VirtualMachine) -> PyObjectRef {